Industries that utilize natural gas, gasifier syngas, biogas, landfill gas, or any type of fuel gas can benefit from knowing the composition of a fuel gas mixture in real-time. Natural gas, the most common fuel, can have significant variation in hydrocarbon composition in areas supplied by multiple sources. The “opportunity fuels” such as biogas and landfill gases, also have significant variation in quality, and operators often use natural gas as a backup fuel.  There is a need for a sensing system that is able to quickly and reliably identify, characterize, and determine the concentration of the various gases in a gas mixture.

The current invention meets this need by providing a gas sensor system capable of accurate and continuous readout of the relative mole percent of all major fuel-gas components including H₂, CO, CO₂, CH₄, C₂H₆, and C₃H₈, along with O₂, N₂, and water vapor. The sensor system is based on Raman spectroscopy, and has been developed to utilize low laser powers and low-resolution spectrometers and detectors to reduce cost while giving readouts in 1 second or less. This sensor system will greatly benefit the power industry, as well as other industries utilizing gaseous input or output streams by enabling faster, smarter control to increase process efficiency and reduce emissions. Currently, NETL is testing field prototype sensor systems  to demonstrate use in applications and long-term operation.